Mark 9:40 (Berean study Bible)
For whoever is not against us is for us.
To be for the Lord and with Him is not merely agreeing with Him, but also disagreeing with everything that the Lord despises. For example, the Lord despises all kinds of perversion (Rev 22:15). Civil democracies, on the other hand, have institutionalized perversions like adultery and homosexuality. If we believers support such immorality by either condoning it or supporting those lawmakers who espouse it, then we partake in that sin (Isaiah 5:20). To be with Him we should also hate everything He hates. But we should also be sure to love the sinner while condemning the sin.